Dr. Andy Galpin

This is not a matter of it's impossible physiologically, but are you going to get your best out of it?

Probably not.

Carbohydrates before exercise, probably three or four hours before exercise, if possible, if you're trying to maximize performance, generally looking at something in the neighborhood of 50 to 100 grams of carbohydrates.

that's a huge plus or minus range there.

Three or four hours before we were generally looking at starches, slower digesting, like give it time, not a big spike.

Some people we will tinker with 30 minutes before something in the neighborhood of 50, 60 grams of carbohydrates, maybe a little bit more.

Some people though kind of deal with a glucose double whammy if you do that.

So you gotta be careful.

Um,

what I mean is if you take a whole bunch of fast responding glucose, right?

Things that get in your bloodstream really quickly, right before you start exercising, insulin starts pulling glucose down, muscle starts pulling it as well.

And so blood glucose actually dips.

This is a like, I had a banana and honey right before I started my race.

And then I got two miles in and I felt like death.

Like, okay, you had two mechanisms at the same time that are independent that are bringing it down and blood glucose actually dips quite a bit until the liver has a chance to kick in and bring it back to normalize.

So you'll feel that response pretty often.

So you got to be really careful with easy digesting carbohydrates right before the event and depending on how long it's going to last.

But those are like rough numbers to start with.

In the exercise itself, the numbers you're going to see here, somewhere in the neighborhood of 60 grams up to 100 grams of carbohydrate per hour, which is...

Like if you want to maximize performance, you'll see the data will show you like 80 plus, 80 to 100 grams.